Eli Lilly's experimental obesity drug retatrutide given to a single patient: how the unusual access is being explained

Eli Lilly has given its unapproved obesity drug retatrutide to a single 79-year-old patient through a "compassionate use" program, according to a STAT News investigation published on Tuesday. The disclosure raises questions about pre-approval access to one of the most-watched experimental medicines in the pharmaceutical industry.

Retatrutide is a triple agonist that targets the GLP-1, GIP and glucagon receptors simultaneously. In Phase 2 data, it produced an average weight loss of up to 24 percent of body weight over 48 weeks, positioning it as Lilly's strongest future challenger to Novo Nordisk's Wegovy and to its own marketed product Zepbound. Phase 3 results are expected in early 2027.

STAT reports that Lilly declined to discuss the patient's identity or how the application was approved. In the United States, expanded access (compassionate use) programs allow patients with serious or life-threatening conditions and no approved treatment option to receive investigational drugs with FDA permission.

The use of these programs for obesity drugs is highly unusual. STAT reporters Ed Silverman and Damian Garde noted that compassionate use historically covers late-stage cancer therapies, rare genetic disorders, and neurological conditions such as ALS. An obesity drug entering this channel opens a new debate in the industry.

Lilly's retatrutide trial enrollment in the United States closed at the end of 2024 as the company finalized recruitment for its Phase 3 studies. That meant the clinical-trial pathway was no longer available to the patient; compassionate use was the only remaining route to the drug outside of a study.

STAT emphasized that the patient is 79, which is unusual because the existing safety database for retatrutide covers mostly patients under 65. There are concerns that GLP-1 class drugs may accentuate muscle loss in older patients, particularly when used at the higher doses tested in Phase 2.

Dr Susan Yanovski, a GLP-1 researcher at the US National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), told STAT that "the ethical rules for compassionate use are clear, but its application in a chronic condition like obesity remains contested." The severity of the patient's comorbidities, such as heart failure or diabetes, is the critical question, she said.

The office of Democratic Senator Elizabeth Warren confirmed to STAT that it plans to request documentation from Lilly about the patient's identity and selection process. Warren has long pressed the industry on drug pricing and access inequalities.

A separate strand of attention surrounds speculation that the patient may be former US President Donald Trump. Both STAT and Ars Technica have raised the possibility; representatives for Trump and Lilly have declined to comment. Lilly said in a statement that "we cannot discuss individual patient cases due to privacy laws."

The case may also bear on Lilly's investor narrative, separate from the company's IPO environment. Lilly shares opened down 0.4 percent on Tuesday; analysts do not expect a material move until Phase 3 data is released.